Method for electrocoagulation of liquids

ABSTRACT

An electrocoagulation treatment device includes a plurality of spaced reaction plates disposed within a reaction chamber. A voltage is applied to selected reaction plates to create an electrical field within the electrocoagulation chamber. The plates are arranged vertically which induces a vertical flow of liquid through a device. The device includes various embodiments adapted for use as a large industrial unit, a portable unit or for use within the home. The voltage and amperage of the electrical field chamber may be adjusted by placing selected reaction plates in electrical contact with the voltage source. One embodiment is especially adapted for treatment of oil slop to remove water from the oil, and for treatment of seawater to desalinate the same.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. Ser. No. 11/197,893 filed onAug. 4, 2005, which is a continuation-in-part application of U.S. Ser.No. 10/050,725 filed on Jan. 15, 2002, entitled “Method forElectrocoagulation of Liquids”, now U.S. Pat. No. 7,211,185, which is acontinuation-in-part application of U.S. Ser. No. 09/644,513 filed onAug. 24, 2000 entitled “Method for Electrocoagulation of Liquids”, nowU.S. Pat. No. 6,488,835 which is a divisional application of U.S. Ser.No. 09/259,246 filed on Feb. 26, 1999 entitled “Apparatus forElectrocoagulation of Liquids”, now U.S. Pat. No. 6,139,710, which is acontinuation-in-part application of and claims the benefit of theearlier filed provisional application, Ser. No. 60/076,298 filed on Feb.27, 1998 entitled “Electrocoagulation Device.”

TECHNICAL FIELD

The present invention relates to a method and apparatus for treating aliquid and, more particularly, to a method and apparatus forelectrocoagulation of liquids by electrolytic treatment to causeimpurities in the liquid to be removed or separable.

BACKGROUND ART

It is known in the art to electrolytically treat liquids to allowseparation of a broad range of contaminants including metals, solids,pathogens, colloids and other undesirable substances. Electrolytictreatment involves the use of an electrical field which is applied to aliquid contained in a chamber in order to coagulate and otherwise toallow for removal of impurities found in the liquid. One example of aprior art device and method for electrolytic treatment is disclosed inPCT Publication No. WO 9640591. According to this invention, a wastestream is first passed through a polarizing means having an electricalpotential that is different than ground potential, and then passedthrough an electrocoagulation chamber including a plurality of elongateelectrodes or electrocoagulation blades which have different electricalpotentials in comparison to one another. A plurality of holes areprovided in the electrodes to cause turbulence in the waste streamwhich, in turn, increases the efficiency of the electrocoagulation.Although this device may be adequate for its intended purpose, onedisadvantage of this device is that the torturous flow path of the wastestream as it passes through the device requires the electrodes orelectrocoagulation blades to be of a high strength to withstand the highwater pressure which must be used in order to keep the waste stream fromclogging. Because the blades of these devices have to be significant insize and strength, a limited number of them can be used in a specifiedvolume which reduces the actual surface area available forelectrocoagulation treatment. Additionally, these coagulation bladesrequire higher input line voltages in order to obtain the desiredamperage between the blades in the electrical field because theirsurface area is limited by the high pressure. Smaller plates canwithstand higher pressures, but the ability to maintain a desiredamperage is sacrificed because available blade surface area within anelectrocoagulation device is directly related to the amperage which canbe maintained. Additionally, the torturous path also causes problems dueto trapped gases produced by the electrolytic reaction in the chamberwhich further increases the pressure upon the blades. Accordingly, ahigh powered pump must be used to overcome the natural tendency of thewaste stream to clog within the chamber. This PCT publicationencompasses the same subject matter as disclosed in U.S. Pat. 5,611,907to Herbst, et al. and U.S. Pat. No. 5,423,962 to Herbst, and furtherincludes subject matter not found in these other patents.

Other examples of electrolytic treatment devices are disclosed in U.S.Pat. No. 4,293,400 to Liggett and U.S. Pat. No. 4,872,959 to Herbst, etal. These devices utilize electrodes in the form of metal tubes or pipesbut require great effort in repairing or replacing the tubes. Thisamount of down time is unacceptable for many commercial applications.

U.S. Pat. No. 5,043,050 to Herbst discloses flat electrodes used withina coagulation chamber; however, in order for the apparatus of thisinvention to be used, the edges of the coagulation chamber must betightly sealed. After long periods of use, the seals are difficult tomaintain.

U.S. Pat. No. 3,925,176 to Okert discloses the use of a plurality ofelectrode plates for electrolytic treatment of liquids. However, theseplates are not intended to be removed either as a whole or individually.Furthermore, the device disclosed in this reference cannot be powered ina series electrical connection which is desirable in many circumstances.

U.S. Pat. No. 5,302,273 to Kemmerer discloses an ionic reaction deviceincluding a tubular housing with multiple circular electrode plates forthe treatment of a fluid. Because of the torturous path utilized in thereaction chamber of this device, high pressures are required to move theliquid through the device, and the device appears susceptible toclogging and excessive gas buildup.

One shortcoming of all of the foregoing prior art references is thatthere is no means by which to transform the input line voltage to thevoltage and amperage necessary to optimize the electrocoagulationtreatment without having to use a separate transformer. In other words,the electrocoagulation chambers themselves do not have the capability totransform the input line voltage to a desired voltage and amperagewithin the electrical field of the electrocoagulation device.

Another shortcoming of the prior art which utilizes a torturous flowpath is that the electrodes or electrocoagulation blades requireprecision holes to be cut to allow gaskets to be bolted between theblades in order to withstand the pressure created by the torturous path.Additionally, the blades have to be laser cut with extreme precision inorder to maintain the exact desired path. Deviation from a predeterminedpath can result in clogging due to buildup of coagulated solids bridgingbetween misaligned blades. These manufacturing requirements greatly addto the cost of building an electrocoagulation device.

Another shortcoming of the prior art, which includes many of thosediscussed above, is that the blades are not easily removable forreplacement or cleaning. Particularly for those chambers utilizing atortuous path, a great number of bolts and gaskets are required to keepthem in alignment. Accordingly, these pieces of hardware must be removedin order to replace the blades.

Each of the foregoing disadvantages are overcome by the apparatus andmethod of this invention. Additionally, the apparatus and method of thisinvention achieve other advantages discussed more fully below.

DISCLOSURE OF THE INVENTION

In accordance with one aspect of the present invention, an apparatus forelectrocoagulation of liquids is provided. In its simplest form, thedevice or apparatus includes a housing defining a reaction chamber, anda plurality of spaced reaction plates/blades which are oriented in avertical position within the reaction chamber. An inlet is provided toallow a desired flow of liquid into the reaction chamber and into thegaps or spaces between the blades. An outlet is provided at an elevationhigher than and downstream of the inlet for allowing the liquid to flowfrom the chamber after the liquid has been treated in the chamber.Selected blades connect to electrical leads which carry an input linevoltage. An electrical field is created in the chamber between theelectrically connected blades. The electrical leads may be attached toselected blades in order to provide the reaction chamber with thedesired voltage and amperage to optimize the electrocoagulation of theparticular liquid. The ability to vary voltage and amperage within theelectrical field of the chamber can be achieved without the use of aseparate transformer. The liquid stream flow is in an upward directionthrough the reaction chamber in the gaps between the plates/blades.Accordingly, the outlet is positioned at the higher level above theinlet. A pump may be placed upstream of the inlet in order to provideadditional head for the flow of liquid passing through the apparatus. Aseries of prefilters or other preconditioning means may be placed inline with the pump and also upstream of the inlet in order to removesolids or other materials which may otherwise clog the reaction chamber.A control unit rectifies the incoming AC line voltage to a DC voltage.Electrical leads interconnect the blades to the DC voltage madeavailable by the control unit. In addition to rectifying the incomingline voltage, the control unit may incorporate a number of otherfunctions which helps to control the apparatus, such as a means tocontrol the speed of the pump and a voltmeter and ammeter to monitor theconditions within the chamber. However, the control unit does not need atransformer as the electrical connections made with the blades allow thedesired voltage and amperage therein to be adjusted, as furtherdiscussed below. Additionally, the control unit can be in the form of aprogrammable logic controller which could not only monitor statuscondition inputs, but also produce outputs to control theelectrocoagulation process. For example, the voltage polarity of theelectrical leads extending from the control unit can be reversed basedupon a timing sequence controlled by the controller. As a furtherexample, the control unit can measure the flow rate of the liquid streamand adjust it accordingly by either manipulating the pump speed, oradjusting the flow rate through a valve positioned upstream of theinlet. After the liquid stream has been electrolytically treated, theliquid stream may be passed through a development chamber and/or throughsecondary separation treatment in order to remove the bulk of thecontaminants which still remain in the liquid stream. It is the intentof the electrocoagulation device of this invention to remove the bulk ofcontaminants in secondary separation treatment. Although somecontaminants will fall out of the liquid stream to the bottom of thereaction chamber, it is desirable to treat the liquid within thereaction chamber and then by force of the liquid stream, move thecontaminants to a downstream secondary separation treatment point. Ifthe bulk of the contaminants were allowed to settle out of the liquidstream within the reaction chamber, then the reaction chamber would haveto be cleaned and serviced more frequently. Secondary separationtreatment can be achieved with a number of devices placed downstream ofthe reaction chamber. For example, secondary separation can beaccomplished with clarifiers, filters, centrifugal separators, orcentrifuges. Each of these devices can be used within secondaryseparation as referred to herein, and any one or a combination of thesedevices may be used depending upon the type of liquid stream treated.

In accordance with another aspect of the present invention, a method isprovided for electrocoagulation by electrolytically treating a liquidstream. The method may include the steps of passing the liquid streamthrough a prefilter and pump, and then through the reaction chamber inan upward flow direction. The method further contemplates the steps ofpassing the liquid stream through an outlet of the reaction chamber andthen through a development chamber and/or secondary separation.Additives can be introduced to the liquid stream in order to target theelectrocoagulation of a specific contaminant.

The electrocoagulation chambers in all of the embodiments have theability to transform the power of the rectified incoming line voltage tothe voltage and amperage in the electrical field within the reactionchamber to optimize the electrocoagulation treatment. These transformingelectrocoagulation chambers therefore allow the same power supplyprovided to the electrocoagulation chamber to be used over a wide rangeof the incoming line voltages. Accordingly, a separate transformer isnot required which greatly saves in the cost of implementing anelectrocoagulation device. Also, the ability to transform the power gridvoltage or incoming line voltage enables the invention to be used inmany countries which have differing standard power grid or linevoltages.

According to another aspect of the invention, the chamber can beoperated under a vacuum. By operation under a vacuum, the gas created bythe electrocoagulation process will be removed from the chamber faster.Furthermore, the use of a vacuum upon the chamber will reduce the amountof dissolved air within the liquid stream. There are circumstances inwhich entrained air impedes the electrocoagulation process, dependingupon the type of liquid treated and the contaminants to be removed.Additionally, subjecting the liquid stream to vacuum also enablesbeneficial gases to be dissolved more efficiently in the liquid streambefore or after coagulation. For example, if the amount of oxygendissolved in the liquid stream needs to be increased, the liquid streamcan be passed through a vacuum to remove the dissolved air, then oxygenor ozone can be added back to the liquid stream through a venturi. Asanother example, carbon dioxide could be added to lower the pH of theliquid stream or ammonia can be used in the same way to increase the pHof the liquid stream. Although a vacuum may be utilized, the apparatuscan be operated at atmospheric pressure.

Another benefit of operating the chamber under a vacuum is the removalof volatilized gases and compounds which would normally remain in theliquid stream under higher ambient pressure conditions.

According to another aspect of the invention, a vacuum may be applied tothe apparatus of this invention by a vacuum hood which is placed overthe reaction chamber or, alternatively, the entire reaction chamber maybe placed within a sealed container or pressure vessel whichcommunicates with a source of vacuum. If a pressure vessel is used, notonly can a vacuum be applied, but the chamber may be kept in apressurized state. A pressurized reaction chamber would be advantageousin situations in which the apparatus is placed in line with a municipalwater source which is already under pressure. Accordingly, no pump orother external pressure means would be required to move the liquidstream through the device.

In another aspect of the invention, the amperage and voltage within thechamber can be adjusted by placing a non-conductive blade or shieldbetween electrically connected blades. Such a non-conductive blade orshield can be made of plastic or PVC and can be removed or added to thechamber in the same manner as the conductive blades. The voltage andamperage within the electrical field may also be modified by adjustingthe surface area of an electrically connected blade in contact with theliquid stream. This is achieved simply by raising or lowering anelectrically connected blade in the liquid stream. Thus, the amount ofblade surface area exposed is directly related to the amperage that willtransfer in the electrical field and through the liquid stream.

In another aspect of the invention, turbulence of the liquid stream maybe increased by providing a hydrocyclone or diaphragm-type pump upstreamof the reaction chamber. Turbulence increases the efficiency of theelectrolytic process. Turbulence may also be increased by injecting airinto the liquid stream upstream of the inlet or at the inlet of thereaction chamber.

According to a first preferred embodiment, the device of this inventionmay be configured for use in the home. Alternatively, the size of thefirst embodiment may be increased to a greater scale in a secondembodiment to handle more industrial-type uses which require greateramounts of treated liquid. In a third preferred embodiment, theapparatus of this invention may be modified in a much smaller scale forportable use. In a fourth preferred embodiment, the apparatus of thisinvention may be incorporated within a pressure vessel which is able topressurize or depressurize the environment in which the electrolytictreatment takes place. The third embodiment differs from the otherembodiments in that no flow occurs through the device. Rather, a staticamount of liquid is treated and then removed for consumption. In yetanother preferred embodiment of the invention, the reaction chamber maybe configured so that the reaction plate tabs extend through a bottomportion of the reaction chamber. This configuration allows thedevelopment chamber to extend directly above the reaction chamber. Alsoin this additional embodiment, a secondary separation chamber may beattached directly to the development chamber, therefore providing ahousing which incorporates all three types of chambers within a singledevice.

In yet another preferred embodiment of the present invention, thereaction chamber can be especially configured for handling treatment ofemulsified oils like slop oil. In this embodiment, the liquid stream tobe recovered is the oil and the water is the undesirable substance to beremoved. The water separated from the oil is allowed to drain out thebottom of the chamber while the oil is removed from the elevated outlet.Thus, there is separate flow of the oil and water in two distinct flowpaths within the chamber. In addition, to slop oil, this embodiment isalso especially adapted for desalinating seawater. The salt laden waterdrains from the bottom of the chamber while the fresher water is removedfrom the elevated outlet.

For each of the embodiments of this invention, the electrocoagulationchambers do not utilize a torturous flow path. The elimination of atorturous flow path of the liquid stream allows thinner blades to beused because the pressure within the chamber is less. The use of thinnerblades allows an increased number of blades to be used within a chamber.By increasing the number of blades within the chamber, the surface areaof the blades in contact with the liquid stream is increased whichenhances the electrolytic treatment of the liquid stream. In otherwords, the chemical reactions which take place within the chamber occuron the surfaces of the blades; therefore, increasing the number ofblades within a set volume ensures that greater electrolytic treatmenttakes place. Also, because there is no torturous flow path, gases whichare produced in the electrolytic process will not create air locks whichcould otherwise distort the blades and the chamber, and increase thepressure required to pump a constant liquid stream through the chamber.The simple flow path between the blades from the bottom to the top ofthe chamber allows the gases created by the electrolytic process to riseas bubbles, as a result of their natural buoyancy, which may then freelyescape into the atmosphere or be drawn off by a source of vacuum. Also,the bubbles move in the direction of liquid flow which further preventsclogging and reduces the amount of pressure needed to move the liquidthrough the device.

Because the total surface area of the blades within the chamber isincreased, the electrocoagulation unit can be operated at a minimumpower consumption. In general, electrocoagulation treatment is dependenton the amperage in the electrical field which is in contact with theliquid stream. If the voltage is maintained within the electrical fieldat a threshold level greater than 2 volts, the electrolytic reactionwill take place wherein metal ions from the blades are added to theliquid stream causing the blades to be consumed over time. Voltagewithin the electrical field is usually only a concern if it cannot bemaintained above the 2-volt level. The total surface area of the bladeswithin the chambers of each of the embodiments is increased sufficientlyto maintain the minimum 2-volt threshold while also maintaining theamperage necessary for effective treatment. In other words, theapparatus of this invention can be operated at lower voltages than theprior art which results in reduced power consumption. There is a directrelationship between the voltage which can be maintained in theelectrical field for a given amperage based on the available surfacearea. An increased surface area allows a specified amperage to bemaintained at a lower voltage. For example, if 1 amp were required toeffect treatment of the liquid and, if the larger surface areas of theblades of this invention allow the 1 amp to be maintained at 2 volts,then the power used is only 2 watts. If a prior art blade having asmaller surface area, say by tenfold, requires a voltage of 20 volts tomaintain the 1 amp, then the power consumption would increase to 20watts. As discussed above, the surface area available in the device ofthis invention is much greater than many prior art blades. Typically,prior art blades require precision manufacturing and, therefore, areexpensive to make. Furthermore, these prior art blades had to be kept ata minimum size in order to withstand pressure within the reactionchamber. Overcoming this size limitation cannot be solved simply bymaking the blades thicker as this would in turn decrease available bladesurface area within the reaction chamber. Making the prior art bladeslarger or wider without increasing thickness would require less pressurein the reaction chamber which could result in massive clogging orcomplete flow disruption. Accordingly, the size of such prior art bladeshad to be kept at a minimum.

The apparatus of this invention is capable of treating many types ofliquids to include, without limitation, water, oil, antifreeze, slopoil, and can be used to desalinate seawater.

The foregoing discussed advantages along with others will becomeapparent from a review of the description which follows in conjunctionwith the corresponding Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an electrocoagulation device of thisinvention, with a portion of the side wall broken away, according to afirst embodiment;

FIG. 2 is a fragmentary perspective view, similar to FIG. 1, but furtherillustrating the inside of the reaction chamber, and a removable topcover;

FIG. 3 is a top plan view of FIG. 1 with all of the reaction platesremoved except for one plate, for clarity purposes;

FIG. 4 is a block diagram of the apparatus of this inventionillustrating major components according to a generic embodiment;

FIG. 5 is a greatly reduced scale perspective view of a secondembodiment of the invention which may be used for high volume productionin industrial settings;

FIG. 6 is an exploded perspective view of a third embodiment of theinvention in the form of a portable or travel unit;

FIG. 7 is a perspective view of reaction plates or blades which may beremoved and replaced as a single unit;

FIG. 8 is a greatly enlarged fragmentary plan view of a pair of reactionplates which are secured within corresponding spacers within thereaction chamber;

FIG. 9 is a fragmentary perspective view of a fourth embodiment of theinvention which utilizes a sealed enclosure or pressure vessel tomaintain a desired pressure or vacuum within the reaction chamber;

FIG. 10 is a fragmentary perspective view of a generic reaction chamberand one example of how selected reaction plates may be connected to anincoming rectified line voltage to produce a desired voltage andamperage within the electrical field of the reaction chamber;

FIG. 11 is another fragmentary perspective view of a generic reactionchamber with reaction plates which are connected to the incoming linevoltage in a different configuration in order to provide a differentvoltage and amperage within the electrical field of the reactionchamber;

FIG. 12 is a fragmentary perspective view of another preferredembodiment of the invention with portions of the electrocoagulationdevice broken away to better illustrate the features therein;

FIG. 13 is another fragmentary perspective view similar to FIG. 12, butillustrating the device in a reversed position, and further illustratinga plurality of reaction plates positioned with the reaction chamber andthe top cover placed over the device;

FIG. 14 is a greatly enlarged partial vertical section illustrating aplurality of reaction plates and selected reaction plates with reactionplate tabs which extend downwardly for allowing connection to a powersource;

FIG. 15 is an enlarged perspective view of a reaction plate whichincludes a reaction plate tab;

FIG. 16 is another fragmentary perspective view of a modification to theembodiment shown in FIG. 12;

FIG. 17 is a side view taken along line 17-17 of FIG. 16 illustratingthe modification; and

FIG. 18 is a fragmentary perspective view of another preferredembodiment utilizing a drain for removal of water from an oil stream orfor removal of salt laden water in desalinating seawater.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates an electrocoagulation device 10 according to thefirst embodiment of the invention. This particular embodiment isrepresentative of the type of device which may be used for treatment ofwater in the home. The device 10 includes a reaction chamber 12 definedby side walls 14. A waste collection base 16 is connected to the chamberhousing 12 by upper flange 18 of reaction chamber 12 and by acorresponding mating lower flange 20 of the base 16. Disposed above thereaction chamber 12 is a collection chamber or development chamber 22.As shown, the collection chamber 22 is wider and deeper than thereaction chamber 12, but is shorter in height. The collection chamber 22is defined by a plurality of side walls 24 and a bottom wall 36, asshown in FIG. 3, which attaches directly to side walls 14. A pluralityof reaction plates or blades 26 are disposed within the reaction chamber12. As shown, the reaction plates 26 extend vertically within thereaction chamber and are placed side-by-side so that there are smallgaps between opposing faces of each of the plates. Selected reactionplates 26 may have integral plate tabs 27 which extend above the sidewalls 24. Although FIG. 1 shows each of the reaction plates 26 as havinga corresponding plate tab, it will be understood that only selectedreaction plates are needed with corresponding plate tabs 27, as furtherdiscussed below. An inlet tube 28 allows the liquid stream to enter thedevice 10 near the bottom thereof. An outlet tube or pipe 32 is providedat the upper portion of the device 10. As shown in FIG. 3, the outlettube 32 is secured to outlet opening 34 which is formed in bottom wall36. Accordingly, the flow of liquid through the device is upward throughthe gaps between the plates 26, over the upper edge 37 of side walls 14and into the collection chamber 22. The liquid stream then exits throughoutlet tube 32. As the electrolytic process takes place, it may benecessary to remove some solids or sludge which precipitate out of theliquid stream and which are not carried by the liquid stream out of thereaction chamber. Accordingly, base 16 includes a drain 38 to removethese materials as well as to provide a means to drain the liquid inorder to clean or service the reaction chamber. The liquid streamentering the device through inlet tube 28 may be evenly distributedbetween the reaction plates 26 by a plurality of openings 29 which aredisposed along the portion of the tube 28 within the reaction chamber.

As shown in FIG. 2, an optional top cover 42 may be provided to preventdirect access to the reaction chamber. Depending upon the amperagewithin the reaction chamber, the top cover acts as a safety device toprevent someone from inadvertently making contact with the reactionplates or the liquid stream. Additionally, a foam cover 40 in the formof a :flat piece of Styrofoam® or other appropriate material may firstbe placed over the reaction plates with openings to allow the plate tabs27 to protrude therethrough. The top cover 42 may also have a continuousopening or plurality of slots 46 in order to allow the reaction tabs toprotrude therethrough. A foam extraction tube 44 is also provided toallow the foam to be extracted from the device during operation.

As best seen in FIGS. 2, 3 and 8, a set of upper spacers 47 and a set oflower spacers 48 are provided as guides for the proper positioning ofthe reaction plates 26. FIG. 3 illustrates all of the blades/plates 26being removed except for one plate in order to better view the interiorof the reaction chamber. As seen in FIG. 8, spacers 47 and 48 are simplyslotted guides which allow the ends 49 of the reaction plates to besecured therein. The spacers are made of a non-conductive material. Theslotted guides ensure that some gap G is maintained between the plates.As shown in FIG. 8, the plates are substantially parallel to oneanother.

In the present invention, the liquid pressure which is experienced bythe reaction plates 26 is minimal in comparison to most prior artdevices. Since the device may be vented to the atmosphere, gases whichare produced in the electrolytic process do not add pressure to theliquid pressure produced by the liquid stream. Such gases form asbubbles and rise within the liquid by buoyancy. The bubbles create foamwhich can be easily removed. Therefore, the strength of the blades isnot a significant consideration and more pure metals may be used in theblades which may not have high strength characteristics in comparison toalloys. Additionally, since the reaction plates operate in a lowerpressure environment, their life is extended since the plates will notprematurely break apart due to excessive pressure. As discussed above,since the blades may also be made thinner, a greater number of platesmay be used within a given volume. Accordingly, the number of gapsbetween the blades is increased which in turn increases the exposurearea of the liquid stream to electrolytic treatment.

In order to remove the reaction plates 26, they may simply be liftedupward and out of the reaction chamber along spacers 47 and 48. Thespacers 47 and 48 provide a simple means by which the plates may besecured and replaced without excessive additional hardware whichotherwise could make replacement of the plates more difficult.

In order to better facilitate the dislodgement of air bubbles which arecreated during the electrolytic process, the reaction chamber may befitted with a device which emits a sonic or radio frequency. This device(not shown) could simply be attached to the side walls 14 andcommunicating with the interior of the reaction chamber.

As shown in FIG. 4, a generic apparatus of this invention is provided inblock diagram format to illustrate major components, and also to betterillustrate the method of the invention. The untreated liquid 51 may bepumped by pump 53 into the inlet 28, or the untreated liquid may beadded directly to the reaction chamber 12 if already under pressure asis the case with municipal water. The untreated liquid 51 may also bepassed through a prefilter 52 to remove solids. The liquid stream entersthe reaction chamber 12 and undergoes electrolytic treatment. A controlunit 54 provides a rectified line voltage to the reaction plates byelectrical leads 56. Electrical leads 56 attach to selected plate tabs27. The liquid stream exits the outlet 32 and may be passed through adevelopment chamber 60. A recycling line 58 can be used to reintroduce adesired portion of the liquid stream for further treatment. In the caseof the first embodiment of FIGS. 1-3, the development chamber 60 is inthe form of the collection chamber 22 which allows foam produced by therising gases to be removed. In other embodiments, the developmentchamber 60 provides additional opportunity for the liquid stream to betreated with additives or other chemicals to condition the liquid forultimate use. Secondary separation means 62 may be placed downstream ofthe development chamber 60 in order to separate and filter outcontaminants or coagulated materials prior to use of the treated liquidstream.

FIG. 5 illustrates a second preferred embodiment of the apparatus of theinvention. This embodiment operates under the same principles as thefirst embodiment, but simply illustrates an alternative arrangementwhich is more suited for situations in which high volumes of treatedliquids are required in industrial settings. As shown, theelectrocoagulation device 70 of this embodiment includes a raw oruntreated liquid tank 72 which receives a supply of liquid through inlet73. A reaction tank 74 and a treated liquid tank 76 are arrangedside-by-side with the untreated liquid tank 72. A pump 80 forces theuntreated liquid through pump lines 82 into the reaction tank 74. A foamcover 84 and a safety top cover 86 are positioned over the reaction tank74 as shown. A safety switch 88 may be incorporated within the upper lip89 of the reaction tank 74 in order to warn a user if the top cover isremoved. The safety switch 88 may be any industrial contact or limitswitch which is wired to the control unit 94. As shown, the control unit94 is mounted to the reaction tank 74 for easy access. Reaction plates90 are placed within the reaction tank 74 and, like the firstembodiment, extend vertically through the reaction tank and arepositioned in spaced apart relation. There are an increased number ofplates in this embodiment in comparison to the first embodiment.Accordingly, this embodiment will require a higher incoming line voltagesuch as 440 volts which is readily available in most industrialsettings. The first embodiment would normally operate at 110 voltsincoming line voltage which is the most common incoming line voltage forresidential areas. Spacers like those used in the first embodiment(spacers 47/48) can also be incorporated within this embodiment tosecure the plates. A plurality of reaction plate tabs or extensions 92extend above the foam cover 84. Electrical leads 96 extend from thecontrol unit 94 and attach to the reaction plate tabs or extensions 92.As with the first embodiment, selected ones of the reaction plates 90may be provided with the reaction plate extensions 92 in order to createthe desired amperage and voltage within the electrical field of thereaction tank. A wier or spillway 98 allows the liquid stream to exitthe reaction tank 74. The foam cover allows the reaction plateextensions 92 to pass therethrough, but forces the foam and liquidstream to flow out of the chamber over the spillway 98. The top cover 86will cover all of the electrical connections for safety purposes. Theelectrical leads 96 may connect to the respective reaction plateextensions by any well-known means such as alligator clips or connectingterminals that are used on industrial batteries. The open area betweenthe foam cover 84 and the spillway 98 allows the foam to be vacuumed offor otherwise removed as desired. The treated liquid accumulating withinthe treated liquid tank 76 may be stored or removed as needed.

In a third preferred embodiment of the invention, a portableelectrocoagulation device 100 is provided as shown in FIG. 6. Thisportable device 100 may be used in those circumstances in which there isno potable water available and a small amount of water is needed fordrinking, cooking or other similar purposes. This embodiment differsfrom the previous embodiments in that there is no liquid flow throughthe device, rather, treatment of a static and predetermined amount ofliquid is achieved. The device 100 includes a reaction chamber 102 whichhouses a plurality of reaction plates 104 which extend verticallythrough the reaction chamber and are spaced apart from one another.Selected reaction plates 104 may include tabs 106 that extend above theupper surfaces of the plates 104. Spacers/dividers 107 are provided tomaintain the reaction plates in their spaced apart relation. The tabs106 each include integral electrical terminals 108 in the form of anelectrical receptacle part. A top cover 116 having a sealing means 118around the lower edge thereof is used to cover the device 100. Anaccessory housing 110 is mounted to the reaction chamber. The accessoryhousing 110 may include a voltage source, such as a battery 112.Electrical leads 113 interconnect the battery 112 with electricalreceptacle parts 109 that are mounted to the underside of the top cover116. When the top cover 116 is mounted over the device 100, electricalreceptacle parts 108 and 109 align and mate with one another thuscompleting an electrical connection between the battery 112 and the tabs106. Electrical receptacle parts 108 could be male receptacles, whilereceptacle parts 109 could be female receptacles, as shown. Receptacles108 and 109 help to protect a user from a potential shock hazard byisolating the electrical connections from contact with the user. Theaccessory housing 110 may also be used to store additional electricalcables or leads 114 which could be used to interconnect a source orpower to the device 100, such as from a vehicle battery After the liquidhas been treated, the liquid may be extracted through spout 120. Afilter 122 is provided to filter out any solids or contaminants. Asshown, the filter 122 may simply be attached to the inside surface ofthe top cover 116. The top cover 116 may be made of a flexible material,and the sealing means 118 may be in the form of a Tupperware® type sealto prevent leakage of liquid.

In operation of the portable electrocoagulation device 100, the topcover is removed, the liquid is simply added to the reaction chamber 102and the voltage is introduced to the reaction plates 104 by battery 112,or another power source interconnected by cables 114. The electrolyticprocess is allowed to occur over a predetermined period of time basedupon the type of liquid being treated and the targeted contaminants tobe removed. The treated liquid is then accessed by opening spout 120. Inorder to more easily remove the treated liquid, a small pump 121 may beprovided which is mounted to the chamber 102. The pump would pressurizethe chamber enabling liquid to pour through the spout 120 more easily.The pump 121 could be a manual primer pump, similar to those used toprime the combustion chambers in small engines. Accordingly the pump 121is shown as including a button 122 which is depressed repeatedly untilthe chamber is so pressurized to allow liquid to pour from the spout.Alternatively, the pump 121 could be an electrically powered pump, andthe battery 112 could be used to power the pump.

It is contemplated that this particular embodiment would be capable oftreating at least 9 oz of water per batch. This embodiment preferablycontains six reaction plates or blades which are removable. The filter122 may be a 16-24 micron filter which is also removable for cleaning.This portable electrocoagulation unit has effectively treated water froman outdoor stream to produce a pathogen free water. In one laboratorytest, total coliform, E. coli, and enterococcus were all reduced toacceptable levels (less than 10 most probable number (mpn)) wherein suchpathogens originally were found at 12,000, 120 and 83 mpn, respectively.In addition to the pathogens discussed above, it is well-known in theart that electrocoagulation and filtration is also effective in theremoval of metal ions, suspended solids, pesticides, herbicides, andcolloidal particles.

As shown in FIG. 7, when it is necessary to remove and replace theblades/reaction plates in any one of the embodiments, either individualblades or the entire set of blades used within the device can beremoved. If the entire set of blades is be removed, a plurality ofnon-conductive rods 126 can be used to interconnect the reaction plates.The non-conductive rods 126 could be sized to fit within the specificreaction chamber used. These rods would serve not only to stabilize theplates within the reaction chamber, but also to keep the reaction platesseparated from one another the desired gap G. For illustration purposes,the gap G between the respective reaction plates 26 has been increasedin order to better illustrate how the reaction plates can be secured toone another through the rods 126. Use of non-conductive rods 126 wouldeliminate the need for use of spacers 47/48. As also shown in FIG. 7,the orientation of the reaction plates can be configured such that platetabs 27 are positioned to allow easy connection to the electrical leads.Placing the tabs in an alternating arrangement helps to prevent theleads from becoming crossed or tangled.

Yet another embodiment of the apparatus of this invention is shown inFIG. 9. In this embodiment, the electrocoagulation device 130 can bemaintained in a pressurized or depressurized environment by a reactionchamber housing 132 which is completely sealed from the environment. Thereaction chamber housing 132 can be any well-known type of pressurevessel which is able to withstand both pressure and vacuum. Thisparticular embodiment is advantageous for use in those situations inwhich the liquid stream is found in a pressurized state, such as amunicipal water supply. Use of the reaction chamber housing 132 wouldtherefore eliminate the need for a pump or some other means to force theliquid stream through the device 130. The principle of operation forthis particular embodiment is the same as the first and secondembodiments wherein a liquid stream passes through the device. Aplurality of reaction plates 134 extend vertically through the reactionchamber, and are in spaced apart relationship. A selected number ofreaction plate tabs or extensions 136 extend upwardly beyond thosereaction plates 134 without tabs. An inlet 138 communicates with thebottom portion of the reaction chamber housing 132. A foam dome orchamber 140 is disposed above the reaction chamber housing 132 in asealed relationship therewith. A foam extraction pipe 142 communicateswith the upper end of the foam dome 140. A liquid stream outlet 144 isattached to the foam dome 140 above the reaction chamber 132 and belowthe foam extraction pipe 142. As the liquid stream exits the reactionchamber through outlet 144, it may then be passed through a venturi 146in order to add a desired gas to the liquid stream such as oxygen. Aventuri feed line 148 allows the desired gas to enter venturi 146.Accordingly, the downstream side of the venturi 146 at pipe 149 containsa mixture of the treated liquid stream and the added gas from feed line148. The addition of oxygen or other gases may help in the treatment ofthe liquid stream. In addition to a particular gas, chemicals or otheragents may be added to the liquid stream at this point to further treatthe liquid. A control unit 150 provides a rectified line voltage to thereaction plates by means of electrical leads 152. Electrical leads 152connect with sealed connections 154 which are electrically coupled totheir corresponding reaction plate tabs 136. Although only a pair ofreaction plate tabs 136 are illustrated, it shall be understood that theamperage and voltage within the reaction chamber may be altered as withthe previous embodiments by providing additional sealed connections 154in conjunction with corresponding selected reaction plate tabs 136.These sealed connections 154 make contact with leads 152 externally ofthe reaction chamber housing 132. The electrocoagulation device of FIG.9 may be followed downstream by a development chamber and a three-phasecentrifugal separator (not shown) or a back washing filter (not shown).This type of treatment is ideal for a home, hot tub or any applicationwhere liquid treatment is needed in a pressurized system. Contaminantscan be removed from the liquid stream and the cleaned liquid can flow asneeded without disruption.

A source of vacuum (not shown) may be connected to foam pipe 142 toassist in removing foam which builds up within foam dome 140. The foamcreated by the electrolytic process will collapse, thus reducing itsvolume during extraction through pipe 142. Application of such a vacuummay also be used to assist in the removal of contaminants from theliquid, before, during or after electrocoagulation, or to enable agreater saturation of beneficial gases in the liquid. For example, theliquid stream within the reaction chamber could be saturated with aparticular gas such as oxygen or carbon dioxide which is provided byanother inlet formed in the reaction chamber (not shown), or the gascould be added directly to the existing inlet. Use of the vacuum tocreate a lower pressure environment would allow such gases to more fullysaturate the liquid stream as it passes through the coagulation chamber.The foam dome 140 may also serve as a distillation tower allowing theseparation of various components from the liquid stream.

In each of the embodiments, the shape of the blades is not critical.Although the preferred embodiments illustrate the blades as havingrectangular shapes, it shall be understood that they can be modified tofit the particular shape and size of the reaction chamber being used.The bottom ends or portions of the blades may be tapered with respect tothe upper ends or upper portions. Tapering of the blades in this mannermakes the blades easier to remove and replace within a reaction chamber.Also, while the blades of this invention are illustrated as beingsubstantially planar, it will be understood that the apparatus andmethod of this invention do not require the blades to be of anyparticular shape. The major concern with regard to the shape of theblades is that the blades will allow the liquid stream to move throughthe reaction chamber in primarily an upward manner so that gasesproduced in the electrolytic reactions can be removed from the liquidstream. Therefore, it is not the intent to provide horizontal or crossflow through the reaction chamber by the use of apertures or openings inthe plate, as is the case with many prior art devices. However, it willbe understood that openings or apertures can be a feature of the bladesof this invention which will not create the horizontal or cross flow.For example, the plates could be manufactured from a screen-likematerial wherein there are a number of openings or holes along thelength of the blade. Again, however, the purpose of these holes oropenings are not for inducing horizontal flow, but are rather forpurposes of providing flexibility in the type of material to be used asthe blades. It is even contemplated within the scope of this inventionthat a heap or pile of metallic material could be placed within thechamber and which would allow the desired electrolytic reactions to takeplace without inducing undesirable horizontal flow.

In the preferred embodiments, the spacing of the blades may be as closeas ⅛″. The closer the blades are together, the greater the surface areamade available for electrocoagulation to occur within a given volume.However, the closer the blades are placed together, the more difficultit becomes to force liquid through the gaps between the blades, and themore likely that clogging could occur between the blades by bridging ofsolid particles or sludge. The thickness of the blades is also apractical consideration, the thinner the blades, the greater surfacearea available for electrocoagulation treatment within a given volume.If the blades are too thin, then their increased flexibility make themharder to install. Also, if the liquid being treated requires theaddition of metal ions from the blades, then thicker blades are able tosacrifice metal ions over a longer period of time before dissolving. Asthe blades dissolve, they look similar to a window screen with irregularholes. The electrocoagulation process continues as long as there is asurface for the reaction to occur. With each of the embodiments of thisinvention, an adequate thickness of the blade is ⅛″. The blades can bemade of aluminum, iron, stainless steel, carbon or any conductivematerial. The choice of blade material is based upon the liquid to beelectrocoagulated, the contaminants to be removed from the liquidstream, the material desired to be left within the liquid stream, andthe material to be precipitated out as sludge.

In lieu of the insulated spacers 47/48 and 107, non-conductive strips ofmaterial or washers may be placed between the blades. These alternatetype of spacers may be held in place by non-conductive bolts or othernon-conductive hardware. The gaps or spaces created between the bladesdo not necessarily have to be exactly parallel or uniform. Theelectrocoagulation process is flexible, and as long as a surface area isprovided for contact with the liquid stream, then the electrocoagulationprocess can occur. As a practical matter; however, it is desirable toavoid choke points or comparatively narrow gaps to prevent undesirablebridging of solid particles.

In the first, second and fourth embodiments, the electrically connectedblades rise up past the liquid line and foam discharge, and pass throughthe foam cover and top cover to prevent foam or liquid from reaching theplate tabs. In the third embodiment, the top cover is removed duringtreatment, but the plate tabs are still maintained above the liquid lineto keep them dry. It is necessary to keep the tabs dry so that corrosiondoes not occur.

In each of the embodiments, the electrocoagulation device of thisinvention may also allow a portion of the liquid stream to bypass theelectrical field between the blades without sacrificing the ability ofthe device to effectively treat the liquid stream. The liquid that doesnot pass through the electrical field will still carry electrons becauseof the contact with liquid that has passed through the electrical field.For example, since the device of this invention does not requireprecision cut blades and the blades are intended to be removable fromspacers 47 and 48, a small portion of the liquid stream could bypass theelectrical field by traveling through small gaps between the blade ends49 and the spacers. Therefore, effective treatment of the total volumeof the liquid stream is still achieved as mixing occurs naturallythroughout the reaction only require exposure of a small portion of thetotal liquid within the electrical field, and then the treated andnon-treated liquids are mixed to effect a suitable treatment for theoverall total volume of liquid. Accordingly, as shown in FIG. 4, thedevelopment chamber which is downstream of the reaction chamber may beused for purposes of further mixing treated and non-treated portions ofthe liquid stream which are not mixed during flow through the reactionchamber.

As briefly explained above, the electrocoagulation chambers utilized inthe various preferred embodiments of this invention have the ability totransform the incoming rectified line voltage or power grid voltage tooptimize the electrocoagulation treatment. Traditionally, prior artcoagulation devices use a separate transformer to take the incoming linevoltage, then rectify and transform the line voltage to a voltage orgroup of voltages at which the reaction chamber can operate efficiently.In the present invention, power is obtained directly from the incomingline voltage or power grid, is rectified through a common diode orrectifier within the control unit, and is then transferred directly tothe electrocoagulation chamber. Transformers of the type needed totransform incoming line voltage to usable voltages within a reactionchamber are extremely expensive and, therefore, add a major cost to theoverall cost of manufacturing an electrocoagulation device. Also, suchtransformers are extremely heavy which makes transport and installationmore difficult. When a traditional transformer is used to lower theincoming line voltage to a level acceptable for use in anelectrocoagulation device, the amperage necessary to treat the liquidstream must be transferred from the transformer to the chamber at alower voltage. Because electrical wires are rated, or sized, based uponamperage specifically, and voltage generally, the size and cost of awire capable of safely conducting low voltage and high amperage is muchgreater than wire used to move high voltage and low amperage. That iswhy power companies move electricity through a power grid from ageneration point at high voltages and low amperages, and then transformthe power to low voltages and high amperages near the point of use(i.e., the home or factory location). Therefore, size and costadvantages can be obtained by conducting electricity at a higher voltageand lower amperage.

The potential between the incoming power or line voltage and the bladeswithin the reaction chamber for each of the embodiments can betransformed generally in accordance with the following:

1. Voltage delivered to the chamber with power connections to the firstand last blade (Nos. 1 and 219, as described further below) results intransformation of the incoming line voltage as follows: The voltagewithin the chamber will be the incoming line voltage divided by thenumber of the gaps between the blades. The amperage draw in the chamberwill be the amperage coming from the incoming line voltage.

2. Voltage delivered to the chamber with power connections to everyblade, alternating between positive and negative leads (Table 2 below)results in transformation of the incoming line voltage as follows: Thevoltage within the chamber will be the incoming line voltage and theamperage will be the total amperage coming from the incoming linevoltage divided by the number of gaps between the blades.

3. The amount of amperage pulled from the incoming line voltage can becontrolled by adjusting the surface area of the electrically connectedblades. There is a linear relationship between the surface area and theamperage pulled; for example, amperage will be doubled if the surfacearea of the electrically connected blades in contact with the liquid isdoubled.

4. The amperage and voltage created within the chamber may be controlledby connecting the incoming line voltage to the blades in any combinationas described above in Nos. 1, 2, and 3. As shown in Table 1, this allowsfor a wide range of amperage and voltage control between the blades.

A set of practical examples will now be described in terms of how theelectrocoagulation device of this invention may transform incoming linevoltage to the amperage and voltage needed within the electrical field.Referring to FIGS. 10 and 11, and Table 1 below, a reaction chamber 160includes a plurality of reaction plates or blades. A control unit 162provides the incoming rectified line voltage by means of positive lead164 and negative lead 166. There are a total of 219 blades within thechamber made of ⅛″ aluminum strap, and spaced ⅛″ apart. The blades ofthis example could be approximately 6″ wide and 48″ long. Assuming thatthe incoming line voltage is traditional three-phase 440 volts AC, adiode or rectifier within the control unit 162 rectifies the linevoltage of 440 volts AC to 560 volts DC (according to standard formulasfor rectifiers wherein the rectified DC voltage equals the AC voltagemultiplied by the square root of 2 and minus 10% rectifier loss). Theleads 164 and 166 attach to respective reaction plate tabs above theliquid line so that the connections are made in a dry location. UsingOhm's law where voltage equals amperage multiplied by resistance, andassuming the resistance is equal to the distance between the blades withvoltage connections, the following table can be generated:

TABLE 1 Transforming By Attaching Leads To Selected Blades Blade WithBlade With Exam- Positive Negative Amperage Voltage Incoming ple LeadLead Between Between Line No. Attached Attached Blades Blades Amperage 1#1 #219 10  2.6 (560/218) 10 2 #1 & 219 #110 20  5.1 (560/109) 40 3 #1 &146 #73 & 219 30  7.7 (560/72) 90 4 #1, #55 & 126 40 10.4 (560/54) 160110, & 219 5 #1, #44, 50 13.0 (560/43) 250 87, & 174 131, & 219 6 #1,73, #36, 60 16.0 (560/35) 360 145, & 219 109, & 182 7 #1, 62, #31, 93,70 18.7 (560/30) 490 125, & 187 156, & 219 8 #1, 55, 109, #27, 82, 8021.5 (560/26) 740 164, 219 136, & 191

FIG. 10 illustrates the electrical connections between the control unitand the reaction chamber according to example 3 of Table 1. As shown,positive lead 164 is attached to blades 168 and 172, which correspond toblade numbers 1 and 145, respectively. The negative lead 166 is attachedto blades 170 and 174 which correspond to blade numbers 73 and 219. Withthis connection configuration, the amperage between each of the bladesis 30 amps. The voltage between each of the blades is 7.7 volts(rectified DC voltage of 560 volts divided by the number of gaps betweenpairs of blades having power applied thereto which in this case is 72).In other words, power is applied to blade numbers 1, 73, 145 and 219,which effectively splits the chamber into three major areas denoted byreference numbers 178, 180 and 182. Therefore, 219 divided by 3 separatearea equals 72 gaps between pairs of electrically connected blades, and560 divided by 72 equals 7.7. Also as shown in Table 1, theelectrocoagulation chamber will pull 90 amps form the incoming linevoltage source.

FIG. 11 illustrates the connections corresponding to example 2 of Table1, as shown, the positive lead 164 is attached to plates 168 and 174corresponding to plate number 1 and 219, respectively. The negative lead166 is attached to blade 176 corresponding to blade number 110.Accordingly, the amperage between each of the blades is 20 amps, thevoltage between the blades is 5.1 volts (560 volts divided by 109). Inother words, the voltage between the blades is the supplied DC voltagedivided by the number of gaps between pairs of electrically connectedblades. As shown in FIG. 11, placement of the electrical leads at bladenumbers 1, 110 and 219 effectively splits the chamber into two majorareas shown as areas 184 and 186. Also in this example, theelectrocoagulation chamber will pull 40 amps from the incoming linevoltage source. Table 1 shows eight different types of connections whichcan be used to obtain different voltages and amperages within thereaction chamber. It is apparent that other voltages and amperages canbe created within the reaction chamber by developing other connectionconfigurations.

Table 2 below illustrates the method by which prior art devices areconfigured for providing an incoming line voltage source to a reactionchamber. As shown, an electrical connection must be made with each ofthe blades within the chamber. A separate transformer then is used toprovide differing incoming line voltages to the chamber. As shown, thecreation of 2.6 volts between each of the blades requires the chamber topull high levels of amperage from the incoming line voltage source. Thisgreater amperage pull requires much larger conductors to be used fortransferring power to the blades in comparison to the apparatus of thisinvention. Additionally, such a prior art devices is more complex andexpensive to manufacture because of the great size and number ofelectrical connections required.

TABLE 2 Prior Art Transforming By Attaching Leads to Each Blade BladeWith Blade With Amperage Voltage Incoming Example Positive NegativeBetween Between Line No. Lead Attached Lead Attached Blades BladesAmperage 1 Odd numbered Even numbered 10 2.6 2,180 2 Odd numbered Evennumbered 20 5.1 4,360 3 Odd numbered Even numbered 30 7.7 6,540 4 Oddnumbered Even numbered 40 10.4 8,720 5 Odd numbered Even numbered 5013.0 10,900 6 Odd numbered Even numbered 60 16.0 13,080 7 Odd numberedEven numbered 70 18.7 15,260 8 Odd numbered Even numbered 80 21.5 17,440

It is also contemplated that the device of this invention can be usedwithin hazardous areas. The electrical connections between the controlunit and the reaction chamber could be insulated in order to conform tostandards for explosion-proof devices. For example, the electricalconnections at the blades could be insulated to include an insulatedcoating placed over the electrically connected blades to a level justbelow the liquid line within the reaction chamber.

With the electrocoagulation device of this invention, the power suppliedto the control unit is set by the incoming line voltage, and theamperage draw is controlled within the electrocoagulation chamber. Theamperage within the electrically connected reaction chamber can becontrolled by (1) adjusting the surface area of the electricallyconnected reaction plates or blades in contact with the liquid stream;(2) adjusting the distance between the electrically connected blades;(3) the addition of non-conductive insulating blades; and (4) adjustingthe conductivity of the liquid by adding chemicals which either enhanceor degrade the ability of the liquid to transfer electrons. Amperage canbe also be controlled by providing a switch between the incoming linevoltage and the reaction chamber which cycles the power “on” and “off.”

As a further discussion of (1) above, the amperage draw can becontrolled inside the reaction chamber by adjusting the liquid contactlength of the electrically connected blades. Using Table 1, Example 1, ablade 6″ wide and 48″ long draws 10 amps with a specific liquid. Theamperage draw of the reaction chamber would be reduced by shorteningblade No. 1 or blade No. 219. The amperage draw would be reduced to 7.5amps if blade No. 1's length was reduced to 36″. The amperage draw wouldbe reduced to 5 amps if blade No. 1's length was reduced to 24″.Therefore, there is a linear relationship between the amperage draw andthe liquid contact length of the electrically connected blades. Theamperage draw can be controlled in the same way by placing anon-conductive blade between electrically connected blades. There is noparticular requirement in terms of the placement of such anon-conductive blade; only that it be placed between designatedelectrically connected blades. The non-conductive blade will reduce theconductivity between the plurality of blades in the reaction chamber inthe same proportion as removing an electrically connected blade fromcontact with the liquid. For example, the amperage draw in the aboveexample would be reduced to 7.5 amps if a non-conductive blade of 12″ inlength were placed in contact with the liquid in the reaction chamberbetween blades Nos. 1 and 219. The amperage draw would be reduced to 5amps if a non-conductive blade 24″ long were placed between blade Nos. 1and 219, and amperage draw would be reduced to 2.5 amps if anon-conductive blade 36″ were placed between blade Nos. 1 and 219. Thelengths of the electrically connected or non-conductive blades can beadjusted in the liquid manually, or mechanically. For example, theinterior surface of the electrocoagulation chamber housing could beprovided with a plurality of vertically adjustable flanges which can beselectively placed at different levels within the reaction chamber andaligned with a particular electrically connected blade. The blade couldbe secured to these vertically adjustable flanges to effectivelyincrease or reduce the surface area of the electrically connected bladein contact with the liquid.

In the first, second and fourth embodiments, the flow of the liquidstream through the chamber could be increased or decreased to furthercontrol the amperage within the reaction chamber. Generally, increasedflow of liquid through the chamber will result in an amperage decreasebecause metal ions from the blades will be removed more quickly therebydecreasing the conductivity of the liquid. As discussed above, thecontrol unit may be equipped with an ammeter to monitor amperage withinthe chamber. The control unit can then control an increase or decreasein the flow rate of the liquid stream through the device by controllinga valve or variable speed pump upstream of the inlet.

In each of the embodiments, the blades over time may be coated with anon-conductive coating or scale. The coating can be removed from theblades by reversing the polarity of the DC power to the electricallyconnected blades. Accordingly, this invention contemplates switching thepolarity of the DC voltage provided to the blades by the control unitaccording to a timed sequence or based on increased amperage whichindicates lower conductivity due to the scaling.

In order to obtain the varying amperages and voltages in Table 1, onlynine blades are required to have plate tabs. Since the blades are easilyremovable, the blades or plates having tabs can be moved to the desiredlocations within the reaction chamber. The foam cover that slips overthe top of the blades through slots cut in the cover will expandallowing the blade to pass through. When a blade is removed, the foamcover will expand to form a water tight seal at the slot.

For the first, second and fourth embodiments, although a top cover isrecommended for safety purposes, the devices will operate without a topcover as long as the connections of the electrical leads occur above theliquid line, thus eliminating typical corrosion problems associated withwet electrode connections.

FIGS. 12-17 illustrate a fifth and sixth preferred embodiment of theinvention. Beginning first with the description of FIG. 12, theelectrocoagulation device 200 can be generally described as an integralhousing which includes not only a reaction chamber 202 and developmentchamber 204, but also a secondary separation chamber 228. Morespecifically, the device 200 has a main chamber including twocomponents, namely, the lower portion defined by reaction chamber 202 inwhich the electrolytic reaction takes place, and the development chamber204 which extends above the upper edges of the reaction plates 218, asshown in FIG. 13. A base portion 206 extends below the reaction chamber202. An inlet tube 208 connects to the base 206 and provides theentering flow of liquid through the device. Optionally, a distributortube 210 can be mounted within the base 206 in order to evenlydistribute the flow of liquid. As shown in FIG. 12, the distributor 210has a plurality of openings formed therein and extends perpendicular tothe inlet tube 208. Another inlet tube 212 can also be provided tointroduce air within the chamber in order to increase turbulence in theflow of liquid. As discussed above, turbulence increases the efficiencyof the electrolytic process in some applications.

Additionally, introduction of turbulence into the liquid stream helps tobreak loose bubbles which form on the surfaces of the reaction plates.Excessive bubbles on the reaction plates hinder the electrolytic processbecause the bubbles reduce the volume of liquid flow through thereaction chamber. Turbulence introduced by air in the liquid streamhelps to break up these bubbles.

The inlet tube 212 communicates with a distributor 214 having aplurality of openings which evenly distributes the introduction of airinto the liquid stream. The distributor 214 can simply be an extensionof inlet tube 212 which passes through an opening in the base 206.Similarly, in lieu of the perpendicular arrangement between tube 208 anddistributor 210, tube 208 may be mounted in the sidewall of the base206, and the distributor 210 can simply be an extension of the tube 208.

The reaction plates 218 are held in their position within the mainchamber by spacers or guides 216 which are mounted on opposing verticalsidewalls of the reaction chamber 202. The spacers 216 shown in thisembodiment extend substantially the height of the reaction plates 218.The lower outside edges of the reaction plates 218 rest upon ledges orflanges 220 which are simply the horizontal extensions formed above base206. A plurality of openings 224 are formed on a lower flange 221 whichis positioned below flange 220. As explained further below, bolts whichmay be connected to a source of power extend through openings 224. Aswith the other embodiments, a predetermined number of reaction platetabs may be provided for the set of reaction plates used within thedevice. The number and spacing of the reaction plate tabs is dictated bythe desired amperage and voltage within the electric field of thereaction chamber. FIGS. 12 and 13 illustrate five openings 224 whichallow five plate tabs 222 connected to corresponding bolts or tabextensions 242 to extend from the device. However, the number ofopenings 224 and corresponding plate tabs 222 can be modified, dependingon the desired characteristics of the electrical field within thereaction chamber 202.

There are a number of advantages of allowing the reaction plate tabs toextend downwardly. One advantage is that a development chamber may beprovided directly above the reaction chamber wherein the developmentchamber simply constitutes an extension of the main chamber of thedevice, the development chamber being defined as a portion of the mainchamber which extends above the upper edges of the reaction plates 218.Another advantage associated with the configuration of the device inFIG. 12 is that caustic conditions known in the art as etching can beminimized which extends the life of the reaction plate tabs. Any timethe reaction plate tabs are subject to an air/liquid line, etching takesplace which results in degradation of the reaction plate tabs, oftencausing them to prematurely break or degrade. Thus, reaction plate tabswhich extend beyond the liquid line and have no protection at theair/liquid line can be subject to etching. One solution to the problemof etchings to simply coat the reaction plate tabs with a non-conductivematerial. However, this adds to the overall expense of the device byhaving to modify the reaction plates themselves. By having the reactionplate tabs contained within the housing and isolated from the amperagein the reaction chamber, the air/liquid line exposure is eliminated,thereby preventing etching.

The device 200 includes the integral secondary separation chamber 228which lies adjacent the development chamber 204. The liquid flows overwier 226 and into the secondary separation chamber 228, and finally theliquid exits the device through outlet 230. A riser tube 232 of aselected height extends from the bottom wall of the secondary separationchamber 228. As the liquid flows over the wier 226 into the chamber 228,secondary separation of contaminants may occur wherein the contaminantscollect on the bottom surface of the chamber 228. The riser tube 232therefore prevents the contaminants from simply flowing through outlettube 230 because many of the contaminants will settle to the bottom ofthe chamber 228. Line 237 represents a typical liquid line duringoperation. Preferably, liquid is allowed to flow over the wier 226 at afairly uniform and constant rate. An upper flange 236 is provided forreceiving the top cover 238. Another advantage of providing reactionplate tabs which extend downwardly into the bottom portion of the deviceis that the construction of the top cover 238 is simplified. That is,there is no requirement for openings or other features on the top cover238. Furthermore, since there are no upward extending reaction platetabs, a user is better able to view the device and observe the flow ofliquid through the device.

Another feature which may be incorporated within the embodiment of FIG.12 is a vacuum tube 234 which may be placed above the liquid line 237,the vacuum tube 234 extending through a selected sidewall of thesecondary separation chamber 228. As with the previous embodiments, foamis created by the electrolytic process and the vacuum tube 234 can beused to facilitate extraction of the foam. Yet another feature that canbe incorporated within the embodiment of FIGS. 12 and 13, as well as anyof the other embodiments, is the use of a sonic cleaning device 250(shown in FIG. 13). Power cord 252 delivers power to the cleaning device250. The device 250 as shown can be placed under the plates and withinthe base 206. The device 250 can be powered by the same power sourcethat delivers electricity to the plate tabs. This device assists in thecleaning of the reaction plates to ensure that the plates did not buildup scale or mineral coatings which degrade the ability of the plates tobe involved with electrocoagulation. Scale referred to herein is acoating or precipitate that becomes deposited on the plates because oftheir contact with minerals or chemicals in the liquid stream. Calciumcarbonate is just one form of scaling that can form on the blades.Electronic scale control units are available which provide small,compact solutions for scale control. These units utilize an oscillatingelectronic field through a modulation frequency waveform to produceinaudible sonic pulses that change the electrical and physicalproperties of scale crystals and other mineral crystals causing thecrystal structures to be repelled from the plates. One commerciallyavailable electronic descaler that can be used is the DCS-100 electronicscaler sold by GI Industries of Monroe, Conn. Over time, it still may benecessary to acid wash the reaction plates 218. The construction of thereaction chamber which utilizes guides 216 to hold the reaction platesenables easy removal of the plates by simply lifting them out of thereaction chamber. If it is necessary to acid wash the reaction plates218 having the tabs 222, bolts 242 must first be removed, and then theplates can be removed. It is also contemplated that the acid wash couldtake place within the reaction chamber with the plates remaining inplace. This in-chamber cleaning requires a temporary shut down of thedevice, and the reaction chamber is filled with the desired acid bath.FIG. 14 illustrates a plurality of reaction plates 218, along withselected reaction plates 218 also having integral plate tabs 222. FIG.15 illustrates a reaction plate 218 including a reaction plate tab 222which has its distal or free end bent at a 90° angle forming a smallflange 240. A hole may be drilled through the flange 240 for receivingthe corresponding bolt or tab extension 242 which attaches thecorresponding electrical conductor 245 to the plate tab 222. In order toseal the plate tabs 222 with respect to the openings 224 formed in thedevice, individual gaskets 244 may be placed below the openings 224which create a water tight seal thereby preventing leakage of fluid. Inlieu of forming a bend or flange 240 in the tabs 222, the bolt could bedirectly welded to the tab on either side thereof. Those skilled in theart can envision other common ways in which the bolts 242 attach totheir respective plate tabs 222.

FIGS. 16 and 17 illustrate one further modification to the embodimentsshown in FIGS. 12 and 13, namely, the addition of plate tab housingextensions 248. As shown in FIG. 17, these extensions 248 are simply cupshaped extensions which extend below ledge 221, and which thereforeisolate the reaction plate tabs 222 from the amperage in the reactionchamber. Extensions 248 also result in larger openings 246 being formedon the ledge 221. It is desirable to limit the exposure of the reactionplate tabs to amperage which will otherwise degrade the reaction platetabs. As with the embodiment shown in FIGS. 12 and 13, since the tabs222 extend below the reaction chamber, they will be isolated from theamperage within the reaction chamber.

In accordance with the method of this invention, treatment of a liquidstream may be achieved by exposing a liquid flow to an electrical field.The flow of the liquid is an upward direction which allows for gaseswhich are produced in the electrolytic reactions to rise to the surfaceof the liquid line and escape to the atmosphere. The bulk of thecoagulated particles are carried to secondary separation and anyremaining particles fall by the force of gravity to the lower portion orbase of the chamber for subsequent removal. The amperage and voltage ofthe electrical field within the electrocoagulation chamber may be variedby connecting the electrical leads to selected plates. Prior to enteringthe chamber, the liquid stream may be filtered, or appropriate chemicalsmay be added to enhance reactions within the chamber. As necessary, apump may be used to force the liquid upwardly through the reactionchamber. Alternatively, the electrolytic reaction may take place in asealed enclosure such as a pressure vessel which may eliminate the needfor a pump if the liquid stream is already under pressure. The use of apressure vessel also allows the electrolytic reaction to take place in avacuum environment wherein a source of vacuum is applied to the chamber.After the liquid stream is exposed to the electrical field and theelectrolytic reactions take place, the liquid stream may be furthertreated in a development chamber and may undergo secondary separation.The turbulence of the liquid stream may be increased prior to enteringthe chamber in order to enhance the electrolytic reactions and to breakloose bubbles which form on the reaction plates. Also as necessary, arecycle line can be provided to recycle the treated liquid stream inorder to provide further treatment.

FIG. 18 illustrates yet another preferred embodiment of the presentinvention. Like reference numbers in this embodiment correspond to thesame items referenced above with respect to the previous embodiments.Slop oil is a water-oil mixture, and is a product produced from oil welloperations. Slop oil is not a commercially usable oil product until thewater is removed. One common process to separate the oil and water oilis through the use of large separator tanks; however, this is a timeconsuming and expensive separation process. Emulsified oils like slopoil can be separated through electrocoagulation. FIG. 18 morespecifically illustrates an electrocoagulation device especially adaptedfor treating slop oil. The inlet tube 208 is preferably located on oneof the vertical sidewalls of the base 206, and a drain tube 260 ispositioned as shown on the most lower surface of the base. Theemulsified oil stream enters the chamber through the inlet tube 208 andthe oil stream passes between the reaction plates. As the oil stream issubjected to electrocoagulation, the emulsion is broken and the waterseparates from the oil. The water attaches to the blades and as thewater builds up on the blades, the water beads up and then runs down theblades into the base 206. Typically, the emulsified oil is bound withwater having a high salt content. As the salt water builds up in thebase of the chamber, if the water volume increases to a point where thesalt water touches the reaction plates, the salt water may short outthose plates because of the high conductivity of the salt water. Toprevent shorting out of the blades by the salt water, theelectrocoagulation device may also incorporate a density switch or floatswitch 262 which is placed in the base of the chamber. The switch 262detects high conductivity, and once the conductivity reached a thresholdlevel, the switch activates the opening of a valve 264 which allows thedrainage of the salt water from within the base 206. Alternatively, theswitch could simply measure water level in the base and be set toactivate the valve when the water level reached the set point.

The oil which no longer is bound to the salt water is able to float tothe top of the chamber and exits through the outlet tube 230. Thus, withtreatment of emulsified oil, there is a distinct counter flow of waterand oil in the electrocoagulation chamber. The emulsified oil enters thechamber, the emulsion is broken causing the water to flow downwardthrough the chamber and through the drain outlet, while the oil floatsand is removed through the outlet tube 230. Depending upon the amount ofwater within the emulsion, as well as the size of the chamber and theeffectiveness of the electrocoagulation in breaking the emulsion, asteady flow of emulsified oil may be treated through theelectrocoagulation device without having to stop or intermittentlyoperate the device.

The size of the base 206 which extends below the blades can also besized to accommodate the anticipated amount of salt water that willseparate from the oil stream. In those circumstances when there is ahigh amount of salt water within the oil stream, the size of the base206 can be increased to accommodate the increased amount of salt waterthat will collect there over time. However, the automatic opening of thevalve 264 by the float switch 262 enables timely draining of the waterto prevent shorting out of the reaction plates. In testing, it has beenfound that the electrocoagulation device of the present invention issuccessful in removing water from the oil stream such that there is lessthan 1% water which remains in the oil stream.

It should also be understood that while this embodiment is shown withthe secondary separation chamber 228, the secondary separation chamberis not necessary and separation of oil and water can be effectivelyconducted within the electrocoagulation chamber 202 and developmentchamber 204. Thus, the outlet 234 could directly communicate with thedevelopment chamber 204.

In summary, in the treatment of an emulsified oil stream, acounter-current flow occurs between the separated oil and water. Theheavier water drops out of the oil stream, and collects at the bottom ofthe chamber. The lighter oil floats to the top of the chamber and isremoved from the outlet. Automatic control is provided to allow drainageof the water build-up by the use of a switch which controls a drainagevalve.

In addition to the treatment of emulsified oil, the embodiment of FIG.18 is also especially adapted for desalinating seawater. Like emulsifiedoil, seawater has a high salt content. The seawater enters the chamberthrough the inlet tube 208 and the seawater passes between the reactionplates. As the seawater is subjected to electrocoagulation, thesalt-laden water attaches to the blades and as the salt-laden waterbuilds upon the blades, the salt-laden water beads up and then runs downthe blades into the base 206. As the salt-laden water builds up in thebase of the chamber, it is undesirable for the salt-laden water to shortout the reaction plates. The float switch 264 discussed above functionsin the same manner with respect to salt-laden water wherein the switchdetects high conductivity and selectively activates the opening of valve264 allowing drainage of the salt-laden water from within the base 206.Alternatively, the switch 262 could simply measure water level in thebase, and can be set to activate the valve when the water level reachesthe set point. Fresh water which has been separated from the salt-ladenwater floats to the top of the chamber and exists through the outlettube 230. Thus, with seawater, there is also a distinct counter flow ofsalt-laden water and fresh water in the electrocoagulation chamber. Thesalt-laden water flows downward through the chamber and through thedrain outlet, while the freshwater flows upward and is removed to theoutlet tube 230. Depending upon the salt content of the seawater, aswell as the size of the chamber and the effectiveness of theelectrocoagulation in separating salt-laden water from fresh water, asteady flow of seawater may be treated through the electrocoagulationdevice without intermittent operation of the device.

By the foregoing, the advantages of the apparatus and method of thisinvention should be apparent. The electrocoagulation chamber has theability to transform incoming line or grid voltage to the voltage andamperage necessary to optimize electrocoagulation treatment. Since thechamber is of simplified construction, the liquid stream does not passthrough a torturous and winding path which therefore eliminates much ofthe liquid pressure. Since the liquid stream travels in an upward paththrough the chamber, gas which is formed in the electrolytic reactionsmay form as bubbles and rise to the top of the liquid level for easyremoval. Additionally, the bubbling action of the gases in the samedirection as the liquid flow prevents gas buildup within the chamberwhich further reduces pressures induced on the blades. The blades of theapparatus are easily removed by the use of spacers which simply alignthe blades with respect to one another in a vertical and side-by-sidefashion. If desired, the chamber can be placed in a sealed enclosuresuch as a common pressure vessel which eliminates the need for a pump ifthe liquid stream supplied is already under pressure. The apparatus ofthis invention may be configured in a portable or travel unit whichmakes it feasible for use in austere conditions. Alternatively, theapparatus of this invention may be made on a much larger scale whichmakes it feasible for use in an industrial setting where greater volumesof treated liquid are required. The blades can be removed individually,or can be removed as an entire set which adds to the versatility of theapparatus.

This invention has been described in detail with reference to particularembodiments thereof, but it will be understood that various othermodifications can be effected within the spirit and scope of thisinvention.

The invention claimed is:
 1. A method of electrocoagulation treatment ofa liquid comprising salinated water, said method comprising the stepsof: providing a housing including a lower portion defining a reactionchamber, a base, and an upper portion defining a development chamber;arranging a plurality of reaction plates within said reaction chamber,the plates being vertically disposed therein and spaced apart from oneanother creating gaps between adjacent reaction plates, said reactionplates being consumed over time due to electrocoagulation taking placewithin said reaction chamber; providing at least a pair of reactionplate tabs connected to selected ones of the plurality of reactionplates, the reaction plate tabs extending through the housing, and thereaction plate tabs being connected to a source of power; applying aline voltage to the at least a pair of reaction plate tabs to create anelectric field within the reaction chamber; passing a stream of thesalinated water vertically through the reaction chamber in the gapsbetween reaction plates; conducting electrocoagulation of the liquidstream to cause the reaction plates to give up ions whereby the reactionplates are consumed over time, resulting in separation of salt-ladenwater from freshwater; collecting salt-laden water droplets on thesurfaces of the reaction plate due to said conducting step; generating aflow of salt-laden water from the surfaces of the reaction plates to thebase thus collecting an amount of salt-laden water in the base;selectively draining the salt-laden water collected in the base; andpassing separated fresh water out of the reaction chamber and through anoutlet.
 2. A method, as claimed in claim 1, further including the stepof: adjusting the voltage and amperage between the reaction plates bychanging the electrical connection between selected ones of the at leasta pair of reaction plate tabs.
 3. A method, as claimed in claim 1,wherein: said selectively draining step is achieved by incorporation ofa drain on said base, and a switch which detects one of the level ofsalt-laden water collecting in said base or the degree of electricalconductivity between plates in contact with the salt-laden water.
 4. Amethod, as claimed in claim 1, wherein: said passing step is continuousand a counter flow of the salt-laden water is drained through the basewhile the separated fresh water passes out of the reaction chamberthrough the outlet.
 5. A method, as claimed in claim 1, furtherincluding: cleaning the housing with a sonic cleaner mounted to saidhousing and communicating with said reaction chamber.
 6. A method, asclaimed in claim 1, wherein: the reaction plate tabs extend through thelower portion of the housing.